Swiss tax return 2026 and 2027: Deadlines, changes and receipts
Swiss tax return 2026 and 2027: cantonal deadlines, what changes for pillar 3a and deductions, and which receipts you should collect now for the 2026 tax year.
In short: With the 2026 tax return you declare the 2025 tax year, with the 2027 tax return the 2026 tax year. In most cantons the deadline is 31 March (Bern and Vaud: 15 March), and Zurich has already confirmed 31 March 2027. New for the 2026 tax year: for the first time you can make up missed pillar 3a contributions from 2025 and deduct them, so collect the receipts for that and for every actual-cost deduction now.
In Switzerland the tax return is named after the year in which you file it, not the year it covers. That causes confusion every year. The 2026 tax return, which you have just finished or are still finishing, covers 2025. The 2027 tax return covers the current year 2026, and whether its receipts are complete is decided right now, in the autumn.
This article sums up the deadlines, names the changes that actually matter for 2026 and 2027 and sets out a timetable through to filing.
When are the 2026 and 2027 tax returns due?
In most cantons the tax return is due by 31 March, in Bern and Vaud by 15 March. What counts is always the date printed on your form or shown in your online access. Self-employed people automatically get more time in several cantons.
| Canton | Deadline private persons | Self-employed | Extension |
|---|---|---|---|
| Zurich | 31 March | automatically to 30 September | free, usually to 30 November |
| Bern | 15 March | 15 May | free online to 15 July |
| Basel-Stadt | 31 March | as stated on the form | free online to 30 September |
| Aargau | 31 March | 30 June | request before the deadline |
| Geneva | 31 March | 31 March | to 31 December, for a fee |
| Vaud | 15 March | 15 March | free, staggered to 30 September |
These values apply to the 2026 tax return (2025 tax year). For the 2027 tax return, Zurich has so far published 31 March 2027. The other cantons rarely change their deadlines; the exact date is on the documents you receive in January or February 2027.
Important when asking for an extension: submit the request before the deadline expires. If you are late you get a reminder, which costs a fee in some cantons.
What changes for the 2027 tax return?
The main change for the 2026 tax year concerns pillar 3a, the Swiss tax-advantaged private pension. Since 2025, the new rules of the pillar 3a ordinance (Art. 7a BVV 3) apply: if you did not pay in the full amount in a year, you can make up the gap later, up to 10 years back, but only for gaps from 2025 onwards. The first back payment is therefore possible in 2026, and it is deductible in the year you pay it, so in the 2027 tax return.
The conditions are strict: in the year of the back payment you must be eligible for pillar 3a, meaning you have earned income subject to AHV, and you must already have paid in the full regular maximum for that year. The maximum amounts for 2026 are CHF 7,258 with a pension fund and 20 percent of earned income, at most CHF 36,288, without one. The money must be credited by 31 December. Your bank or insurer provides the receipt with the pillar 3a certificate.
Other values for the 2026 tax year in the direct federal tax:
- The deduction for commuting costs stays capped at CHF 3,300. The cantons have their own limits.
- The flat rate for other professional expenses is 3 percent of net salary, at least CHF 2,000 and at most CHF 4,000.
- If you deduct actual costs instead of flat rates, you need a receipt for every item.
Decisions made in referendums take effect later: the imputed rental value (Eigenmietwert) on owner-occupied homes is abolished from 1 January 2029, and individual taxation comes into force on 1 January 2032. Nothing changes for the 2026 and 2027 tax returns. Homeowners deduct maintenance costs as usual until then and still need the invoices.
Which receipts should you collect for 2026 now?
For the 2027 tax return you need the receipts for the whole of 2026, and most get lost between October and December. Certificates from your employer, bank and pillar 3a provider arrive by themselves in January. What is missing is almost always the everyday receipts.
The most important categories:
- Professional expenses, if you deduct actual costs rather than the flat rate: tools, specialist books, work clothes, home office equipment
- Further training: course invoices and proof of payment
- Medical costs: dentist, glasses, pharmacy, health insurance cost sharing
- Donations to tax-exempt organisations
- Childcare: nursery, after-school care, childminder
- Property maintenance: tradespeople's invoices, service charges
- For the self-employed: all business receipts, expenses and investments
The full tick-off list is in the receipts checklist for the Swiss tax return, and which deductions exist at all is covered in Tax deductions in Switzerland.
A timetable through to filing in March 2027
If you want to finish the tax return in one evening, spread the work over three short slots. A realistic routine looks like this:
- October to December 2026: photograph and categorise every new receipt straight away. Ask for missing receipts from the spring now, while your doctor or course provider still remembers.
- By 31 December 2026: pay into pillar 3a and check whether a back payment for 2025 applies to you. Plan any spending above a deductible threshold for December if it makes sense.
- January 2027: collect your salary certificate, bank statements and pillar 3a certificate. Export the 2026 tax year.
- February to March 2027: fill in the tax return, upload receipts as PDFs, request an extension if needed.
For the first step your phone is enough. Belego saves every receipt as a PDF, reads the amount, date and merchant and files it in a category that you match to the relevant item of the tax return. In December the year overview shows how much has built up per category. In January you export 2026 as a ZIP with every PDF and a CSV list, or as a PDF report with totals per category; you can upload either directly or send it to your Treuhänder (the Swiss term for an accountant or trustee). How to wrap up the year in three steps is explained in Year-end receipts.
What applies to the self-employed?
Besides the tax return, self-employed people submit their annual accounts or, for smaller businesses, a statement of income, expenses, assets and private withdrawals. For that they need every business receipt of the year, not just the deductible ones.
Several cantons therefore give the self-employed more time, for example Zurich automatically to 30 September, Bern to 15 May and Aargau to 30 June. If you work with a Treuhänder, hand over your receipts early anyway, because spring is their busiest season. What your Treuhänder needs exactly is explained in Self-employed in Switzerland: receipts, expenses and bookkeeping.
Note: This article is general guidance, not tax advice. What counts is the law, the cantonal guidance and the information from your tax authority or your Treuhänder.
Frequently asked questions
Which year do I declare with the 2027 tax return?
With the 2027 tax return you declare the 2026 tax year, so income, assets and deductions from 1 January to 31 December 2026. Assets are declared as at 31 December 2026. You receive the forms in early 2027, in many cantons only as login details for the online tax return.
Can I deduct a pillar 3a back payment in the 2026 tax return?
No. Back payments are only possible for gaps from 2025 onwards and are deducted in the year you pay them. A back payment made in 2026 for a 2025 gap therefore appears in the 2027 tax return. The condition is that you have already paid the full regular contribution for 2026.
What happens if I miss the deadline?
The tax office sends a reminder with a new deadline, which costs a fee in some cantons. If you still do not file, you are assessed at the tax office's discretion, meaning an estimate, usually not in your favour. It is easier to request an extension online before the deadline, which is free in many cantons.
Do I have to attach every receipt to the tax return?
No. Usually you only attach your salary certificate, pillar 3a certificate, list of securities and, depending on the canton, proof for certain deductions. Keep all other receipts, because the tax office can ask for them at any time. As a private person it is best to keep them for around 10 years.